Gas cooktop



FIG. 1 is a perspective view of a gas cooktop showing my ornamentaldesign;

FIG. 2 is a top plan view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a rear view thereof;

FIG. 5 is a left view thereof;

FIG. 6 is a right view thereof; and,

FIG. 7 is a bottom view thereof.

The ornamental design for a gas cooktop, as shown and described.